1. Field of Invention
The invention relates to an Insulation Displacement Connection (IDC) terminal, and particularly to an IDC terminal that conforms to EIA/TIA Category 6 standards for transmitting high speed electronic signals and has simple structure.
2. Related Art
In recent years network communication systems have become very popular to transmit data, and widely adopted. As the demand grows for high transmission efficiency with network communication systems, not only higher quality connection lines are required, but also higher quality connectors are required with transmission speed increased. In general, a network communication path consists of a transmission medium and transmission connectors. The transmission medium may be a Twisted Pair, Coaxial Cable, Optical Fiber, etc. The network communication path mentioned above still has drawbacks. Signal quality often deteriorates as the frequency of the network communication system increases. For instance:
1. Near-End Cross Talk (NEXT) phenomenon: When two cables are close to each other and generate induction, interference occurs due to electromagnetism, and Cross Talk phenomenon takes place.
2. Impedance phenomenon: The impedance of the transmission medium has to match the system to transmit signals effectively.
3. Return Loss phenomenon: As the impedance of the transmission system is not continuous, reflections occur and power loss results.
4. Attenuation phenomenon: When the signals are transmitted via the transmission medium, signal intensity and power decay with signal traveling distance.
The standards announced by the Electronic Industries Association (EIA) and TIA are adopted by IEEE. EIA/TIA 568 standards have been included in 802.3u standards. Hence the parameters of transmission media and connectors require confirming these standards, and those conforming to the standards are categorized. At present, Category 6 standards have gradually become the basic requirements. Thus it is necessary to overcome the problems previously discussed.
The conventional IDC terminal assemblies, as shown in FIG. 1, includes IDC terminals 11 arranged in parallel to the longitudinal axis of a terminal seat 12. The IDC terminals 11 are equally spaced with one another. Each pair of IDC terminals 11 is interfered with by the neighboring IDC terminals 11. As a result, transmission quality is not desirable. To remedy this problem, many schemes have been proposed. For instance, Siemon Co. proposes to use a metal shield, as shown in FIG. 2A. It has four pairs of IDC terminals 11 that are spaced from one another at a greater interval, and each pair of IDC terminals 11 has a shielding blade 13. The shielding blade 13 of any two pairs of neighboring IDC terminals 11 reduces interference. However, the size of the IDC terminal assembly increases significantly. Material and production costs also are higher. Panduit Co. proposes a technique with IDC terminals of the same pair arranged staggered on two rows in a front side and rear side fashion. Hence any three neighboring IDC terminals 11 are spaced from one another at about the intervals. Such a design allows any two pairs of neighboring IDC terminals 11 to have TT compensation effect, as shown in FIG. 2B. However, the thickness T of the IDC terminal assembly increases, and the communication core lines cannot be installed by a general wiring machine. U.S. Pat. No. 6,648,670 discloses a design with IDC terminals spaced from one another at an unequal interval. The interval of one pair of terminals is smaller than the interval of the neighboring IDC terminals of different pair. A diagonal assembly and an extending blade are adopted to enhance the compensation effect between different pairs of terminals of the same line position attribute. Its diagonal assembly design can reduce the thickness of the total IDC terminal structure. However, the wiring machine has to be altered to wire the communication core to adopt the design of the diagonal assembly and unequal intervals. Moreover, the corresponding connectors also have to be changed. The connectors adopted in the conventional IDC terminal assembly cannot be used.